CN105967791A - Water-soluble silicate slow-release fertilizer and preparation method thereof - Google Patents

Abstract

The invention discloses a water-soluble silicate slow-release fertilizer and a preparation method thereof. The water-soluble silicate slow-release fertilizer is prepared from the following raw materials (by weight): rice hull, 20wt% NaOH solution, attapulgite powder, peat soil, potassium sulfate, oxalic acid, urea, zinc sulfate, sodium fulvate, ammonium molybdate and a proper amount of water. Rice hull ash contains lots of silica. After an alkaline solution is added into the rice hull ash and the mixture is heated, a silicate component which can be absorbed by plants is obtained. The silicate is beneficial to plant germination, rooting and seedling growth. The extraction method is simple and reliable and is simple to implement. Rice hull is crushed into particles with a certain particle size, and the particles are carbonized to obtain a carbonized product with particles similar to activated carbon adsorption principle. As silica on the particles is consumed during the reaction process, pores will be left, which is more beneficial to adsorption function of the carbonized product. Thus, utilization rate of the fertilizer is increased.

Description

A kind of water-soluble silicate slow release fertilizer and preparation method thereof

Technical field

The invention belongs to the Technology field of fertilizer, be specifically related to a kind of water-soluble silicate slow release fertilizer and preparation method thereof.

Background technology

Along with expanding economy, chemical fertilizer is increasing in usage amount agriculturally.And crops are low to the utilization rate of chemical fertilizer, utilization rate fertile for N is 30 ~ 35%, utilization rate fertile for P is 10 ~ 20%, the most inevitably cause the environmental pollution of chemical fertilizer, additionally, the Soil structure destruction and the soil fertility that use chemical fertilizer institute band class decline, and the problem of body eutrophication is irreversible.

Element silicon is one of important element necessary to crop growth, the research of element silicon is the most increasingly paid attention to by people, and research is introduced and confirmed: element silicon has that enhancing crop plant stem stalk is sturdy, resistant to lodging, improves disease resistance, anti-soil soil nutrient physiological stress, increase the characteristic such as yield.And rice husk absorbs a large amount of silicon in the growth and development process of Oryza sativa L. from soil, its dioxide-containing silica is up to more than 20% more than, in China, rice husk is a kind of very abundant plant material, and industry uses phosphoric acid method, alkali method to prepare activated carbon, sodium silicate and all achieve certain success.

The most existing a lot of scholars made in-depth study with regard to the problem of rice hull ash, burned the difference of degree according to rice husk, and rice husk ash composition is also not quite similar.Rice husk is after burning completely, carbon therein discharges with the form of carbon dioxide, silicon therein is changed into silicon dioxide, so the carbon produced is not completely transformed into carbon dioxide, therefore in black particle shape, from the point of view of the present Research of comprehensive rice hull ash, the high silicon content that point of penetration is rice hull ash of these researchs and bigger serface.Utilize rice hull ash to react with Caustic soda and produce sodium silicate, production of silica white is reacted with ammonium sulfate, boil rear synthesizing silicon carbide with acid, extract silicon dioxide therein and to utilize rice hull ash to produce the research such as concrete high activity admixture be this characteristic of high silicon content based on rice hull ash.

Summary of the invention

In order to improve the germination percentage of crop seed, promoting growth and the growth of root system of crop seedling, fertilizer of the present invention contains silicates fertilizer as the one used before crop-planting and possesses all above feature, realizes particular by following methods:

A kind of water-soluble silicate slow release fertilizer, it is characterized in that, be made up of the raw material of following weight portion: rice husk 40 ~ 45,20wt%NaOH solution 120 ~ 150, attapulgite 15 ~ 20, peat soil 30 ~ 45, potassium sulfate 20 ~ 26, oxalic acid 5 ~ 10, carbamide 20 ~ 25, zinc sulfate 2 ~ 4, sodium fulvate 10 ~ 15, ammonium molybdate 3 ~ 6 and appropriate water；

The preparation method of a kind of water-soluble silicate slow release fertilizer, it is characterised in that include following step:

(1) rice husk is first pulverized, be ground into the granule of 10 ~ 20 mesh sieves, put in Muffle furnace, under airtight condition, be heated to temperature 600 ~ 800 DEG C, continue carbonization 6 ~ 8h and obtain carbonizing production；

(2) by the carbonizing production mixing 20wt%NaOH solution described in (1), put in reactor, be heated to 100 ~ 120 DEG C, insulation reaction 4 ~ 5h, must be rich in the carbonizing production of silicate；

(3) mixing potassium sulfate, oxalic acid, carbamide and other following residual components being not directed to, add the water of 3 ~ 5 times of its total weight parts, and heated and stirred, to being completely dissolved, is subsequently adding the carbonizing production described in (2), and stirring 40 ~ 55min adsorbs；

(4) Mixed Concave convex rod powder and peat soil, adds in always expecting to the mixing described in (3), is milled to homogenate, and finally control moisture is at the thickness thickener of 40 ~ 50%, by slurry-spraying pelletizing, makes the granule of particle diameter 3 ~ 5mm.

Rice hull ash is utilized by the present invention by emphasis, it is critical only that the silicate using alkali-soluble acid analysis technology that the amorphous silicon in rice hull ash is converted into easy solvent, then test variable concentrations silicon pretreatment is to seed vitality, Root Absorption ability and the impact of young leaflet tablet chlorophyll content, the silicate solubility that test is optimum.

Rice husk is after pyrolysis or burning, and contained silicon is with SiO₂Presented in rice hull ash, through spectrum analysis, siliceous 28%, be converted into SiO₂Content is 60%, and phosphorus content is 39%, the SiO in rice husk₂Can react with soda bath under the conditions of temperature-pressure and generate silicate product:

SiO₂+2NaOH→Na₃SiO ₂+H₂O

Activated carbon is the pore structure with prosperity, has the charcoal of the biggest specific surface area and absorbability, rice hull ash i.e. the rice husk product after carbonization, and phosphorus content improves to more than 90%, and carbonaceous is loose porous, is the excellent material manufacturing activated carbon.The present invention is before this by rice husk drying and crushing, obtain the rice husk granule of certain particle diameter, then the overall Muffle furnace putting into high temperature, adjust temperature and carry out carbonization, must have the activated carbon structure material of certain absorbability, then the NaOH solution that mass fraction is 20% is added, under certain temperature conditions, the reaction regular hour obtains the rice hull ash product containing certain silicate content, simultaneously, rice hull ash also has a lot of granular active carbon granules, there is certain adsorption of modification effect, as the additive of fertilizer, give the probability that fertilizer variation is wireless.

Owing to the high temperature carbonization of Muffle furnace prepares the process of activated carbon granule, carry out under conditions of airtight starvation, consume again certain SiO subsequently with the course of reaction of soda bath₂, consuming SiO₂During on granule, leave again hole, add specific surface area and the space structure of granule, advantageously in adsorption process, proved by test repeatedly: NaOH solution and rice hull ash material ratio are 3:1, response time about 4h, when reaction temperature is 100 DEG C, the optimum dissolution rate obtaining silicate reaches 90.47%.

Beneficial effects of the present invention: containing substantial amounts of silicon dioxide in rice hull ash, by obtaining the silicate component of plant available after adding aqueous slkali heating, silicate is conducive to the germination of plant, take root, the growth of seedling, extracting method is simple and reliable, carry out simple, then by pulverizing the granule that powdered rice hulls is broken into certain particle diameter, carry out carbonization process again, reach graininess and be similar to the carbonizing production of activated carbon adsorption principle, owing to the silicon dioxide on granule has consumed during reaction, so hole can be left, it is more beneficial for the adsorption function of carbonizing production, improve utilization rate of fertilizer.

Detailed description of the invention

Embodiment 1:

A kind of water-soluble silicate slow release fertilizer, it is characterized in that, be made up of the raw material of following weight portion (Kg): rice husk 40,20wt%NaOH solution 120, attapulgite 16, peat soil 45, potassium sulfate 20, oxalic acid 6, carbamide 25, zinc sulfate 4, sodium fulvate 10, ammonium molybdate 5 and appropriate water；

The preparation method of a kind of water-soluble silicate slow release fertilizer, it is characterised in that include following step:

(1) rice husk is first pulverized, be ground into the granule of 10 ~ 20 mesh sieves, put in Muffle furnace, under airtight condition, be heated to temperature 600 ~ 800 DEG C, continue carbonization 6 ~ 8h and obtain carbonizing production；

(2) by the carbonizing production mixing 20wt%NaOH solution described in (1), put in reactor, be heated to 100 ~ 120 DEG C, insulation reaction 4 ~ 5h, must be rich in the carbonizing production of silicate；

(3) mixing potassium sulfate, oxalic acid, carbamide and other following residual components being not directed to, add the water of 3 ~ 5 times of its total weight parts, and heated and stirred, to being completely dissolved, is subsequently adding the carbonizing production described in (2), and stirring 40 ~ 55min adsorbs；

(4) Mixed Concave convex rod powder and peat soil, adds in always expecting to the mixing described in (3), is milled to homogenate, and finally control moisture is at the thickness thickener of 40 ~ 50%, by slurry-spraying pelletizing, makes the granule of particle diameter 3 ~ 5mm.

Claims (2)

1. a water-soluble silicate slow release fertilizer, it is characterized in that, be made up of the raw material of following weight portion: rice husk 40 ~ 45,20wt%NaOH solution 120 ~ 150, attapulgite 15 ~ 20, peat soil 30 ~ 45, potassium sulfate 20 ~ 26, oxalic acid 5 ~ 10, carbamide 20 ~ 25, zinc sulfate 2 ~ 4, sodium fulvate 10 ~ 15, ammonium molybdate 3 ~ 6 and appropriate water.

The preparation method of a kind of water-soluble silicate slow release fertilizer, it is characterised in that include following step:

(1) rice husk is first pulverized, be ground into the granule of 10 ~ 20 mesh sieves, put in Muffle furnace, under airtight condition, be heated to temperature 600 ~ 800 DEG C, continue carbonization 6 ~ 8h and obtain carbonizing production；

(2) by the carbonizing production mixing 20wt%NaOH solution described in (1), put in reactor, be heated to 100 ~ 120 DEG C, insulation reaction 4 ~ 5h, must be rich in the carbonizing production of silicate；

(3) mixing potassium sulfate, oxalic acid, carbamide and other following residual components being not directed to, add the water of 3 ~ 5 times of its total weight parts, and heated and stirred, to being completely dissolved, is subsequently adding the carbonizing production described in (2), and stirring 40 ~ 55min adsorbs；

(4) Mixed Concave convex rod powder and peat soil, adds in always expecting to the mixing described in (3), is milled to homogenate, and finally control moisture is at the thickness thickener of 40 ~ 50%, by slurry-spraying pelletizing, makes the granule of particle diameter 3 ~ 5mm.